Syslinux - Feb 2014 - [PATCH] efi: Suspicious size reduction in emalloc

From: Sylvain Gault <sylvain.gault at gmail.com>

I found something suspicious while hunting another bug a while ago.  The
conditions for that bug to occur seems quite hard to meet, but it's still
code
quality improvement. See the commit message for details.

Sylvain Gault (1):
  efi: Suspicious size reduction in emalloc

 efi/main.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

-- 
1.8.5.3

From: Sylvain Gault <sylvain.gault at gmail.com>

It could happen on 32 bits architecture that the memory size really allocated
could be less than required. On 64 bits, allocate_pages may be called
more times than needed.

This closes bug #39.

Signed-off-by: Sylvain Gault <sylvain.gault at gmail.com>
---
 efi/main.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/efi/main.c b/efi/main.c
index 0e6b137..94878f9 100644
--- a/efi/main.c
+++ b/efi/main.c
@@ -691,10 +691,8 @@ EFI_STATUS emalloc(UINTN size, UINTN align,
EFI_PHYSICAL_ADDRESS *addr)
 		/* Low-memory is super-precious! */
 		if (end <= 1 << 20)
 			continue;
-		if (start < 1 << 20) {
-			size -= (1 << 20) - start;
+		if (start < 1 << 20)
 			start = (1 << 20);
-		}
 
 		aligned = (start + align -1) & ~(align -1);
 
-- 
1.8.5.3

2014-02-13 3:20 UTC+01:00, celelibi at gmail.com <celelibi at
gmail.com>:
> From: Sylvain Gault <sylvain.gault at gmail.com>
>
It looks like git-send-email messed the headers when changing the sender.

Op 2014-02-13 om 04:04 schreef Sylvain Gault:
> 2014-02-13 3:20 UTC+01:00, celelibi at gmail.com <celelibi at
gmail.com>:
> > From: Sylvain Gault <sylvain.gault at gmail.com>
> >
> 
> It looks like git-send-email messed the headers when changing the sender.
And there was no actual patch ( no unified diff output ) in that e-mail.

Please rerun providing '[PATCH] Potential bug in emalloc'


Groeten
Geert Stappers
-- 
Leven en laten leven

On Wed, Feb 12, 2014 at 9:20 PM,  <celelibi at gmail.com>
wrote:
> From: Sylvain Gault <sylvain.gault at gmail.com>
>
> It could happen on 32 bits architecture that the memory size really
allocated
> could be less than required. On 64 bits, allocate_pages may be called
> more times than needed.
>
> This closes bug #39.
>
> Signed-off-by: Sylvain Gault <sylvain.gault at gmail.com>
> ---
>  efi/main.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/efi/main.c b/efi/main.c
> index 0e6b137..94878f9 100644
> --- a/efi/main.c
> +++ b/efi/main.c
> @@ -691,10 +691,8 @@ EFI_STATUS emalloc(UINTN size, UINTN align,
EFI_PHYSICAL_ADDRESS *addr)
>                 /* Low-memory is super-precious! */
>                 if (end <= 1 << 20)
>                         continue;
> -               if (start < 1 << 20) {
> -                       size -= (1 << 20) - start;
> +               if (start < 1 << 20)
>                         start = (1 << 20);
> -               }
>
>                 aligned = (start + align -1) & ~(align -1);
Geert, it looks like the thread got broken apart

-- 
-Gene

2014-02-13 4:04 UTC+01:00, Sylvain Gault <sylvain.gault at
gmail.com>:
> 2014-02-13 3:20 UTC+01:00, celelibi at gmail.com <celelibi at
gmail.com>:
>> From: Sylvain Gault <sylvain.gault at gmail.com>
>>
>
> It looks like git-send-email messed the headers when changing the sender.
>
Actually this was correct. It's the git-send-email way to specify the
author when it's different from the mail sender. And git-am will parse
it correctly and generate the right "Author:".


Celelibi